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diff --git a/texinfo/info/info.texi b/texinfo/info/info.texi new file mode 100644 index 00000000000..efc3077e339 --- /dev/null +++ b/texinfo/info/info.texi @@ -0,0 +1,929 @@ +\input texinfo @c -*-texinfo-*- +@comment %**start of header +@setfilename info.info +@settitle Info 1.0 +@comment %**end of header +@comment $Id: info.texi,v 1.1 1997/08/21 22:58:02 jason Exp $ + +@ifinfo +@c This is a dir.info fragment to support semi-automated addition of +@c manuals to an info tree. +@format +START-INFO-DIR-ENTRY +* info: (info). Reading GNU online documentation. +END-INFO-DIR-ENTRY +@end format +@end ifinfo + +@iftex +@finalout +@end iftex +@dircategory Texinfo documentation system +@direntry +* Info: (info). Documentation browsing system. +@end direntry + +@ifinfo +This file describes how to use Info, +the on-line, menu-driven GNU documentation system. + +Copyright (C) 1989, 92, 96 Free Software Foundation, Inc. + +Permission is granted to make and distribute verbatim copies of +this manual provided the copyright notice and this permission notice +are preserved on all copies. + +@ignore +Permission is granted to process this file through TeX and print the +results, provided the printed document carries copying permission +notice identical to this one except for the removal of this paragraph +(this paragraph not being relevant to the printed manual). + +@end ignore +Permission is granted to copy and distribute modified versions of this +manual under the conditions for verbatim copying, provided that the entire +resulting derived work is distributed under the terms of a permission +notice identical to this one. + +Permission is granted to copy and distribute translations of this manual +into another language, under the above conditions for modified versions, +except that this permission notice may be stated in a translation approved +by the Free Software Foundation. +@end ifinfo + +@titlepage +@sp 11 +@center @titlefont{Info} +@sp 2 +@center The +@sp 2 +@center On-line, Menu-driven +@sp 2 +@center GNU Documentation System + +@page +@vskip 0pt plus 1filll +Copyright @copyright{} 1989, 1992, 1993 Free Software Foundation, Inc. +@sp 2 + +Published by the Free Software Foundation @* +59 Temple Place - Suite 330 @* +Boston, MA 02111-1307, USA. + +Permission is granted to make and distribute verbatim copies of +this manual provided the copyright notice and this permission notice +are preserved on all copies. + +Permission is granted to copy and distribute modified versions of this +manual under the conditions for verbatim copying, provided that the entire +resulting derived work is distributed under the terms of a permission +notice identical to this one. + +Permission is granted to copy and distribute translations of this manual +into another language, under the above conditions for modified versions, +except that this permission notice may be stated in a translation approved +by the Free Software Foundation. +@end titlepage + +@ifinfo +@node Top, Getting Started, (dir), (dir) +@top Info: An Introduction + +Info is a program for reading documentation, which you are using now. + +To learn how to use Info, type the command @kbd{h}. It brings you +to a programmed instruction sequence. + +@c Need to make sure that `Info-help' goes to the right node, +@c which is the first node of the first chapter. (It should.) +@c (Info-find-node "info" +@c (if (< (window-height) 23) +@c "Help-Small-Screen" +@c "Help"))) + +To learn advanced Info commands, type @kbd{n} twice. This brings you to +@cite{Info for Experts}, skipping over the `Getting Started' chapter. +@end ifinfo + +@menu +* Getting Started:: Getting started using an Info reader. +* Advanced Info:: Advanced commands within Info. +* Create an Info File:: How to make your own Info file. +* The Standalone Info Program: (info-stnd.info). +@end menu + +@node Getting Started, Advanced Info, Top, Top +@comment node-name, next, previous, up +@chapter Getting Started + +This first part of the Info manual describes how to get around inside +of Info. The second part of the manual describes various advanced +Info commands, and how to write an Info as distinct from a Texinfo +file. The third part is about how to generate Info files from +Texinfo files. + +@iftex +This manual is primarily designed for use on a computer, so that you can +try Info commands while reading about them. Reading it on paper is less +effective, since you must take it on faith that the commands described +really do what the manual says. By all means go through this manual now +that you have it; but please try going through the on-line version as +well. + +There are two ways of looking at the online version of this manual: + +@enumerate +@item +Type @code{info} at your shell's command line. This approach uses a +small stand-alone program designed just to read Info files. + +@item +Type @code{emacs} at the command line; then type @kbd{C-h i} (Control +@kbd{h}, followed by @kbd{i}). This approach uses the Info mode of the +Emacs program, an editor with many other capabilities. +@end enumerate + +In either case, then type @kbd{mInfo} (just the letters), followed by +@key{RET}---the ``Return'' or ``Enter'' key. At this point, you should +be ready to follow the instructions in this manual as you read them on +the screen. +@c FIXME! (pesch@cygnus.com, 14 dec 1992) +@c Is it worth worrying about what-if the beginner goes to somebody +@c else's Emacs session, which already has an Info running in the middle +@c of something---in which case these simple instructions won't work? +@end iftex + +@menu +* Help-Small-Screen:: Starting Info on a Small Screen +* Help:: How to use Info +* Help-P:: Returning to the Previous node +* Help-^L:: The Space, Rubout, B and ^L commands. +* Help-M:: Menus +* Help-Adv:: Some advanced Info commands +* Help-Q:: Quitting Info +@end menu + +@node Help-Small-Screen, Help, , Getting Started +@comment node-name, next, previous, up +@section Starting Info on a Small Screen + +@iftex +(In Info, you only see this section if your terminal has a small +number of lines; most readers pass by it without seeing it.) +@end iftex + +Since your terminal has an unusually small number of lines on its +screen, it is necessary to give you special advice at the beginning. + +If you see the text @samp{--All----} at near the bottom right corner +of the screen, it means the entire text you are looking at fits on the +screen. If you see @samp{--Top----} instead, it means that there is +more text below that does not fit. To move forward through the text +and see another screen full, press the Space bar, @key{SPC}. To move +back up, press the key labeled @samp{Backspace} or @key{Delete}. + +@ifinfo +Here are 40 lines of junk, so you can try Spaces and Deletes and +see what they do. At the end are instructions of what you should do +next. + +This is line 17 @* +This is line 18 @* +This is line 19 @* +This is line 20 @* +This is line 21 @* +This is line 22 @* +This is line 23 @* +This is line 24 @* +This is line 25 @* +This is line 26 @* +This is line 27 @* +This is line 28 @* +This is line 29 @* +This is line 30 @* +This is line 31 @* +This is line 32 @* +This is line 33 @* +This is line 34 @* +This is line 35 @* +This is line 36 @* +This is line 37 @* +This is line 38 @* +This is line 39 @* +This is line 40 @* +This is line 41 @* +This is line 42 @* +This is line 43 @* +This is line 44 @* +This is line 45 @* +This is line 46 @* +This is line 47 @* +This is line 48 @* +This is line 49 @* +This is line 50 @* +This is line 51 @* +This is line 52 @* +This is line 53 @* +This is line 54 @* +This is line 55 @* +This is line 56 @* + +If you have managed to get here, go back to the beginning with +Delete, and come back here again, then you understand Space and +Delete. So now type an @kbd{n} ---just one character; don't type +the quotes and don't type the Return key afterward--- to +get to the normal start of the course. +@end ifinfo + +@node Help, Help-P, Help-Small-Screen, Getting Started +@comment node-name, next, previous, up +@section How to use Info + +You are talking to the program Info, for reading documentation. + + Right now you are looking at one @dfn{Node} of Information. +A node contains text describing a specific topic at a specific +level of detail. This node's topic is ``how to use Info''. + + The top line of a node is its @dfn{header}. This node's header (look at +it now) says that it is the node named @samp{Help} in the file +@file{info}. It says that the @samp{Next} node after this one is the node +called @samp{Help-P}. An advanced Info command lets you go to any node +whose name you know. + + Besides a @samp{Next}, a node can have a @samp{Previous} or an @samp{Up}. +This node has a @samp{Previous} but no @samp{Up}, as you can see. + + Now it is time to move on to the @samp{Next} node, named @samp{Help-P}. + +>> Type @samp{n} to move there. Type just one character; + do not type the quotes and do not type a @key{RET} afterward. + +@samp{>>} in the margin means it is really time to try a command. + +@node Help-P, Help-^L, Help, Getting Started +@comment node-name, next, previous, up +@section Returning to the Previous node + +This node is called @samp{Help-P}. The @samp{Previous} node, as you see, +is @samp{Help}, which is the one you just came from using the @kbd{n} +command. Another @kbd{n} command now would take you to the next +node, @samp{Help-^L}. + +>> But do not do that yet. First, try the @kbd{p} command, which takes + you to the @samp{Previous} node. When you get there, you can do an + @kbd{n} again to return here. + + This all probably seems insultingly simple so far, but @emph{do not} be +led into skimming. Things will get more complicated soon. Also, +do not try a new command until you are told it is time to. Otherwise, +you may make Info skip past an important warning that was coming up. + +>> Now do an @kbd{n} to get to the node @samp{Help-^L} and learn more. + +@node Help-^L, Help-M, Help-P, Getting Started +@comment node-name, next, previous, up +@section The Space, Delete, B and ^L commands. + + This node's header tells you that you are now at node @samp{Help-^L}, and +that @kbd{p} would get you back to @samp{Help-P}. The node's title is +underlined; it says what the node is about (most nodes have titles). + + This is a big node and it does not all fit on your display screen. +You can tell that there is more that is not visible because you +can see the string @samp{--Top-----} rather than @samp{--All----} near +the bottom right corner of the screen. + + The Space, Delete and @kbd{B} commands exist to allow you to ``move +around'' in a node that does not all fit on the screen at once. +Space moves forward, to show what was below the bottom of the screen. +Delete moves backward, to show what was above the top of the screen +(there is not anything above the top until you have typed some spaces). + +>> Now try typing a Space (afterward, type a Delete to return here). + + When you type the space, the two lines that were at the bottom of +the screen appear at the top, followed by more lines. Delete takes +the two lines from the top and moves them to the bottom, +@emph{usually}, but if there are not a full screen's worth of lines +above them they may not make it all the way to the bottom. + + If you type Space when there is no more to see, it rings the +bell and otherwise does nothing. The same goes for Delete when +the header of the node is visible. + + If your screen is ever garbaged, you can tell Info to print it out +again by typing @kbd{C-l} (@kbd{Control-L}, that is---hold down ``Control'' and +type an @key{L} or @kbd{l}). + +>> Type @kbd{C-l} now. + + To move back to the beginning of the node you are on, you can type +a lot of Deletes. You can also type simply @kbd{b} for beginning. +>> Try that now. (We have put in enough verbiage to push this past +the first screenful, but screens are so big nowadays that perhaps it +isn't enough. You may need to shrink your Emacs or Info window.) +Then come back, with Spaces. + + If your screen is very tall, all of this node might fit at once. +In that case, "b" won't do anything. Sorry; what can we do? + + You have just learned a considerable number of commands. If you +want to use one but have trouble remembering which, you should type +a @key{?} which prints out a brief list of commands. When you are +finished looking at the list, make it go away by typing a @key{SPC}. + +>> Type a @key{?} now. After it finishes, type a @key{SPC}. + + (If you are using the standalone Info reader, type `l' to return here.) + + From now on, you will encounter large nodes without warning, and +will be expected to know how to use Space and Delete to move +around in them without being told. Since not all terminals have +the same size screen, it would be impossible to warn you anyway. + +>> Now type @kbd{n} to see the description of the @kbd{m} command. + +@node Help-M, Help-Adv, Help-^L, Getting Started +@comment node-name, next, previous, up +@section Menus + +Menus and the @kbd{m} command + + With only the @kbd{n} and @kbd{p} commands for moving between nodes, nodes +are restricted to a linear sequence. Menus allow a branching +structure. A menu is a list of other nodes you can move to. It is +actually just part of the text of the node formatted specially so that +Info can interpret it. The beginning of a menu is always identified +by a line which starts with @samp{* Menu:}. A node contains a menu if and +only if it has a line in it which starts that way. The only menu you +can use at any moment is the one in the node you are in. To use a +menu in any other node, you must move to that node first. + + After the start of the menu, each line that starts with a @samp{*} +identifies one subtopic. The line usually contains a brief name +for the subtopic (followed by a @samp{:}), the name of the node that talks +about that subtopic, and optionally some further description of the +subtopic. Lines in the menu that do not start with a @samp{*} have no +special meaning---they are only for the human reader's benefit and do +not define additional subtopics. Here is an example: + +@example +* Foo: FOO's Node This tells about FOO +@end example + +The subtopic name is Foo, and the node describing it is @samp{FOO's Node}. +The rest of the line is just for the reader's Information. +[[ But this line is not a real menu item, simply because there is +no line above it which starts with @samp{* Menu:}.]] + + When you use a menu to go to another node (in a way that will be +described soon), what you specify is the subtopic name, the first +thing in the menu line. Info uses it to find the menu line, extracts +the node name from it, and goes to that node. The reason that there +is both a subtopic name and a node name is that the node name must be +meaningful to the computer and may therefore have to be ugly looking. +The subtopic name can be chosen just to be convenient for the user to +specify. Often the node name is convenient for the user to specify +and so both it and the subtopic name are the same. There is an +abbreviation for this: + +@example +* Foo:: This tells about FOO +@end example + +@noindent +This means that the subtopic name and node name are the same; they are +both @samp{Foo}. + +>> Now use Spaces to find the menu in this node, then come back to + the front with a @kbd{b} and some Spaces. As you see, a menu is + actually visible in its node. If you cannot find a menu in a node + by looking at it, then the node does not have a menu and the + @kbd{m} command is not available. + + The command to go to one of the subnodes is @kbd{m}---but @emph{do +not do it yet!} Before you use @kbd{m}, you must understand the +difference between commands and arguments. So far, you have learned +several commands that do not need arguments. When you type one, Info +processes it and is instantly ready for another command. The @kbd{m} +command is different: it is incomplete without the @dfn{name of the +subtopic}. Once you have typed @kbd{m}, Info tries to read the +subtopic name. + + Now look for the line containing many dashes near the bottom of the +screen. There is one more line beneath that one, but usually it is +blank. If it is empty, Info is ready for a command, such as @kbd{n} +or @kbd{b} or Space or @kbd{m}. If that line contains text ending +in a colon, it mean Info is trying to read the @dfn{argument} to a +command. At such times, commands do not work, because Info tries to +use them as the argument. You must either type the argument and +finish the command you started, or type @kbd{Control-g} to cancel the +command. When you have done one of those things, the line becomes +blank again. + + The command to go to a subnode via a menu is @kbd{m}. After you type +the @kbd{m}, the line at the bottom of the screen says @samp{Menu item: }. +You must then type the name of the subtopic you want, and end it with +a @key{RET}. + + You can abbreviate the subtopic name. If the abbreviation is not +unique, the first matching subtopic is chosen. Some menus put +the shortest possible abbreviation for each subtopic name in capital +letters, so you can see how much you need to type. It does not +matter whether you use upper case or lower case when you type the +subtopic. You should not put any spaces at the end, or inside of the +item name, except for one space where a space appears in the item in +the menu. + + You can also use the @dfn{completion} feature to help enter the subtopic +name. If you type the Tab key after entering part of a name, it will +magically fill in more of the name---as much as follows uniquely from +what you have entered. + + If you move the cursor to one of the menu subtopic lines, then you do +not need to type the argument: you just type a Return, and it stands for +the subtopic of the line you are on. + +Here is a menu to give you a chance to practice. + +* Menu: The menu starts here. + +This menu gives you three ways of going to one place, Help-FOO. + +* Foo: Help-FOO. A node you can visit for fun.@* +* Bar: Help-FOO. Strange! two ways to get to the same place.@* +* Help-FOO:: And yet another!@* + + +>> Now type just an @kbd{m} and see what happens: + + Now you are ``inside'' an @kbd{m} command. Commands cannot be used +now; the next thing you will type must be the name of a subtopic. + + You can change your mind about doing the @kbd{m} by typing Control-g. + +>> Try that now; notice the bottom line clear. + +>> Then type another @kbd{m}. + +>> Now type @samp{BAR} item name. Do not type Return yet. + + While you are typing the item name, you can use the Delete key to +cancel one character at a time if you make a mistake. + +>> Type one to cancel the @samp{R}. You could type another @samp{R} to + replace it. You do not have to, since @samp{BA} is a valid abbreviation. + +>> Now you are ready to go. Type a @key{RET}. + + After visiting Help-FOO, you should return here. + +>> Type @kbd{n} to see more commands. + +@c If a menu appears at the end of this node, remove it. +@c It is an accident of the menu updating command. + +Here is another way to get to Help-FOO, a menu. You can ignore this +if you want, or else try it (but then please come back to here). + +@menu +* Help-FOO:: +@end menu + +@node Help-FOO, , , Help-M +@comment node-name, next, previous, up +@subsection The @kbd{u} command + + Congratulations! This is the node @samp{Help-FOO}. Unlike the other +nodes you have seen, this one has an @samp{Up}: @samp{Help-M}, the node you +just came from via the @kbd{m} command. This is the usual +convention---the nodes you reach from a menu have @samp{Up} nodes that lead +back to the menu. Menus move Down in the tree, and @samp{Up} moves Up. +@samp{Previous}, on the other hand, is usually used to ``stay on the same +level but go backwards'' + + You can go back to the node @samp{Help-M} by typing the command +@kbd{u} for ``Up''. That puts you at the @emph{front} of the +node---to get back to where you were reading you have to type +some @key{SPC}s. + +>> Now type @kbd{u} to move back up to @samp{Help-M}. + +@node Help-Adv, Help-Q, Help-M, Getting Started +@comment node-name, next, previous, up +@section Some advanced Info commands + + The course is almost over, so please stick with it to the end. + + If you have been moving around to different nodes and wish to +retrace your steps, the @kbd{l} command (@kbd{l} for @dfn{last}) will +do that, one node-step at a time. As you move from node to node, Info +records the nodes where you have been in a special history list. The +@kbd{l} command revisits nodes in the history list; each successive +@kbd{l} command moves one step back through the history. + + If you have been following directions, ad @kbd{l} command now will get +you back to @samp{Help-M}. Another @kbd{l} command would undo the +@kbd{u} and get you back to @samp{Help-FOO}. Another @kbd{l} would undo +the @kbd{m} and get you back to @samp{Help-M}. + +>> Try typing three @kbd{l}'s, pausing in between to see what each + @kbd{l} does. + +Then follow directions again and you will end up back here. + + Note the difference between @kbd{l} and @kbd{p}: @kbd{l} moves to +where @emph{you} last were, whereas @kbd{p} always moves to the node +which the header says is the @samp{Previous} node (from this node, to +@samp{Help-M}). + + The @samp{d} command gets you instantly to the Directory node. +This node, which is the first one you saw when you entered Info, +has a menu which leads (directly, or indirectly through other menus), +to all the nodes that exist. + +>> Try doing a @samp{d}, then do an @kbd{l} to return here (yes, + @emph{do} return). + + Sometimes, in Info documentation, you will see a cross reference. +Cross references look like this: @xref{Help-Cross, Cross}. That is a +real, live cross reference which is named @samp{Cross} and points at +the node named @samp{Help-Cross}. + + If you wish to follow a cross reference, you must use the @samp{f} +command. The @samp{f} must be followed by the cross reference name +(in this case, @samp{Cross}). While you enter the name, you can use the +Delete key to edit your input. If you change your mind about following +any reference, you can use @kbd{Control-g} to cancel the command. + + Completion is available in the @samp{f} command; you can complete among +all the cross reference names in the current node by typing a Tab. + +>> Type @samp{f}, followed by @samp{Cross}, and a @key{RET}. + + To get a list of all the cross references in the current node, you can +type @kbd{?} after an @samp{f}. The @samp{f} continues to await a +cross reference name even after printing the list, so if you don't +actually want to follow a reference, you should type a @kbd{Control-g} +to cancel the @samp{f}. + +>> Type "f?" to get a list of the cross references in this node. Then + type a @kbd{Control-g} and see how the @samp{f} gives up. + +>> Now type @kbd{n} to see the last node of the course. + +@c If a menu appears at the end of this node, remove it. +@c It is an accident of the menu updating command. + +@node Help-Cross, , , Help-Adv +@comment node-name, next, previous, up +@unnumberedsubsec The node reached by the cross reference in Info + + This is the node reached by the cross reference named @samp{Cross}. + + While this node is specifically intended to be reached by a cross +reference, most cross references lead to nodes that ``belong'' +someplace else far away in the structure of Info. So you cannot expect +the footnote to have a @samp{Next}, @samp{Previous} or @samp{Up} pointing back to +where you came from. In general, the @kbd{l} (el) command is the only +way to get back there. + +>> Type @kbd{l} to return to the node where the cross reference was. + +@node Help-Q, , Help-Adv, Getting Started +@comment node-name, next, previous, up +@section Quitting Info + + To get out of Info, back to what you were doing before, type @kbd{q} +for @dfn{Quit}. + + This is the end of the course on using Info. There are some other +commands that are meant for experienced users; they are useful, and you +can find them by looking in the directory node for documentation on +Info. Finding them will be a good exercise in using Info in the usual +manner. + +>> Type @samp{d} to go to the Info directory node; then type + @samp{mInfo} and Return, to get to the node about Info and + see what other help is available. + +@node Advanced Info, Create an Info File, Getting Started, Top +@comment node-name, next, previous, up +@chapter Info for Experts + +This chapter describes various advanced Info commands, and how to write +an Info as distinct from a Texinfo file. (However, in most cases, writing a +Texinfo file is better, since you can use it @emph{both} to generate an +Info file and to make a printed manual. @xref{Top,, Overview of +Texinfo, texinfo, Texinfo: The GNU Documentation Format}.) + +@menu +* Expert:: Advanced Info commands: g, s, e, and 1 - 5. +* Add:: Describes how to add new nodes to the hierarchy. + Also tells what nodes look like. +* Menus:: How to add to or create menus in Info nodes. +* Cross-refs:: How to add cross-references to Info nodes. +* Tags:: How to make tag tables for Info files. +* Checking:: Checking an Info File +* Emacs Info Variables:: Variables modifying the behavior of Emacs Info. +@end menu + +@node Expert, Add, , Advanced Info +@comment node-name, next, previous, up +@section Advanced Info Commands + +@kbd{g}, @kbd{s}, @kbd{1}, -- @kbd{9}, and @kbd{e} + +If you know a node's name, you can go there by typing @kbd{g}, the +name, and @key{RET}. Thus, @kbd{gTop@key{RET}} would go to the node +called @samp{Top} in this file (its directory node). +@kbd{gExpert@key{RET}} would come back here. + +Unlike @kbd{m}, @kbd{g} does not allow the use of abbreviations. + +To go to a node in another file, you can include the filename in the +node name by putting it at the front, in parentheses. Thus, +@kbd{g(dir)Top@key{RET}} would go to the Info Directory node, which is +node @samp{Top} in the file @file{dir}. + +The node name @samp{*} specifies the whole file. So you can look at +all of the current file by typing @kbd{g*@key{RET}} or all of any +other file with @kbd{g(FILENAME)@key{RET}}. + +The @kbd{s} command allows you to search a whole file for a string. +It switches to the next node if and when that is necessary. You +type @kbd{s} followed by the string to search for, terminated by +@key{RET}. To search for the same string again, just @kbd{s} followed +by @key{RET} will do. The file's nodes are scanned in the order +they are in in the file, which has no necessary relationship to the +order that they may be in in the tree structure of menus and @samp{next} pointers. +But normally the two orders are not very different. In any case, +you can always do a @kbd{b} to find out what node you have reached, if +the header is not visible (this can happen, because @kbd{s} puts your +cursor at the occurrence of the string, not at the beginning of the +node). + +If you grudge the system each character of type-in it requires, you +might like to use the commands @kbd{1}, @kbd{2}, @kbd{3}, @kbd{4}, ... +@kbd{9}. They are short for the @kbd{m} command together with an +argument. @kbd{1} goes through the first item in the current node's +menu; @kbd{2} goes through the second item, etc. + +If you display supports multiple fonts, and you are using Emacs' Info +mode to read Info files, the @samp{*} for the fifth menu item is +underlines, and so is the @samp{*} for the ninth item; these underlines +make it easy to see at a glance which number to use for an item. + +On ordinary terminals, you won't have underlining. If you need to +actually count items, it is better to use @kbd{m} instead, and specify +the name. + +The Info command @kbd{e} changes from Info mode to an ordinary +Emacs editing mode, so that you can edit the text of the current node. +Type @kbd{C-c C-c} to switch back to Info. The @kbd{e} command is allowed +only if the variable @code{Info-enable-edit} is non-@code{nil}. + +@node Add, Menus, Expert, Advanced Info +@comment node-name, next, previous, up +@section Adding a new node to Info + +To add a new topic to the list in the Info directory, you must: +@enumerate +@item +Create some nodes, in some file, to document that topic. +@item +Put that topic in the menu in the directory. @xref{Menus, Menu}. +@end enumerate + +Usually, the way to create the nodes is with Texinfo @pxref{Top,, Overview of +Texinfo, texinfo, Texinfo: The GNU Documentation Format}); this has the +advantage that you can also make a printed manual from them. However, +if hyou want to edit an Info file, here is how. + + The new node can live in an existing documentation file, or in a new +one. It must have a @key{^_} character before it (invisible to the +user; this node has one but you cannot see it), and it ends with either +a @key{^_}, a @key{^L}, or the end of file. Note: If you put in a +@key{^L} to end a new node, be sure that there is a @key{^_} after it +to start the next one, since @key{^L} cannot @emph{start} a node. +Also, a nicer way to make a node boundary be a page boundary as well +is to put a @key{^L} @emph{right after} the @key{^_}. + + The @key{^_} starting a node must be followed by a newline or a +@key{^L} newline, after which comes the node's header line. The +header line must give the node's name (by which Info finds it), +and state the names of the @samp{Next}, @samp{Previous}, and @samp{Up} nodes (if +there are any). As you can see, this node's @samp{Up} node is the node +@samp{Top}, which points at all the documentation for Info. The @samp{Next} +node is @samp{Menus}. + + The keywords @dfn{Node}, @dfn{Previous}, @dfn{Up}, and @dfn{Next}, +may appear in any order, anywhere in the header line, but the +recommended order is the one in this sentence. Each keyword must be +followed by a colon, spaces and tabs, and then the appropriate name. +The name may be terminated with a tab, a comma, or a newline. A space +does not end it; node names may contain spaces. The case of letters +in the names is insignificant. + + A node name has two forms. A node in the current file is named by +what appears after the @samp{Node: } in that node's first line. For +example, this node's name is @samp{Add}. A node in another file is +named by @samp{(@var{filename})@var{node-within-file}}, as in +@samp{(info)Add} for this node. If the file name starts with ``./'', +then it is relative to the current directory; otherwise, it is relative +starting from the standard Info file directory of your site. +The name @samp{(@var{filename})Top} can be abbreviated to just +@samp{(@var{filename})}. By convention, the name @samp{Top} is used for +the ``highest'' node in any single file---the node whose @samp{Up} points +out of the file. The Directory node is @file{(dir)}. The @samp{Top} node +of a document file listed in the Directory should have an @samp{Up: +(dir)} in it. + + The node name @kbd{*} is special: it refers to the entire file. +Thus, @kbd{g*} shows you the whole current file. The use of the +node @kbd{*} is to make it possible to make old-fashioned, +unstructured files into nodes of the tree. + + The @samp{Node:} name, in which a node states its own name, must not +contain a filename, since Info when searching for a node does not +expect one to be there. The @samp{Next}, @samp{Previous} and @samp{Up} names may +contain them. In this node, since the @samp{Up} node is in the same file, +it was not necessary to use one. + + Note that the nodes in this file have a file name in the header +line. The file names are ignored by Info, but they serve as comments +to help identify the node for the user. + +@node Menus, Cross-refs, Add, Advanced Info +@comment node-name, next, previous, up +@section How to Create Menus + + Any node in the Info hierarchy may have a @dfn{menu}---a list of subnodes. +The @kbd{m} command searches the current node's menu for the topic which it +reads from the terminal. + + A menu begins with a line starting with @samp{* Menu:}. The rest of the +line is a comment. After the starting line, every line that begins +with a @samp{* } lists a single topic. The name of the topic--the +argument that the user must give to the @kbd{m} command to select this +topic---comes right after the star and space, and is followed by a +colon, spaces and tabs, and the name of the node which discusses that +topic. The node name, like node names following @samp{Next}, @samp{Previous} +and @samp{Up}, may be terminated with a tab, comma, or newline; it may also +be terminated with a period. + + If the node name and topic name are the same, then rather than +giving the name twice, the abbreviation @samp{* NAME::} may be used +(and should be used, whenever possible, as it reduces the visual +clutter in the menu). + + It is considerate to choose the topic names so that they differ +from each other very near the beginning---this allows the user to type +short abbreviations. In a long menu, it is a good idea to capitalize +the beginning of each item name which is the minimum acceptable +abbreviation for it (a long menu is more than 5 or so entries). + + The nodes listed in a node's menu are called its ``subnodes'', and +it is their ``superior''. They should each have an @samp{Up:} pointing at +the superior. It is often useful to arrange all or most of the +subnodes in a sequence of @samp{Next} and @samp{Previous} pointers so that someone who +wants to see them all need not keep revisiting the Menu. + + The Info Directory is simply the menu of the node @samp{(dir)Top}---that +is, node @samp{Top} in file @file{.../info/dir}. You can put new entries +in that menu just like any other menu. The Info Directory is @emph{not} the +same as the file directory called @file{info}. It happens that many of +Info's files live on that file directory, but they do not have to; and +files on that directory are not automatically listed in the Info +Directory node. + + Also, although the Info node graph is claimed to be a ``hierarchy'', +in fact it can be @emph{any} directed graph. Shared structures and +pointer cycles are perfectly possible, and can be used if they are +appropriate to the meaning to be expressed. There is no need for all +the nodes in a file to form a connected structure. In fact, this file +has two connected components. You are in one of them, which is under +the node @samp{Top}; the other contains the node @samp{Help} which the +@kbd{h} command goes to. In fact, since there is no garbage +collector, nothing terrible happens if a substructure is not pointed +to, but such a substructure is rather useless since nobody can +ever find out that it exists. + +@node Cross-refs, Tags, Menus, Advanced Info +@comment node-name, next, previous, up +@section Creating Cross References + + A cross reference can be placed anywhere in the text, unlike a menu +item which must go at the front of a line. A cross reference looks +like a menu item except that it has @samp{*note} instead of @kbd{*}. +It @emph{cannot} be terminated by a @samp{)}, because @samp{)}'s are +so often part of node names. If you wish to enclose a cross reference +in parentheses, terminate it with a period first. Here are two +examples of cross references pointers: + +@example +*Note details: commands. (See *note 3: Full Proof.) +@end example + +They are just examples. The places they ``lead to'' do not really exist! + +@node Tags, Checking, Cross-refs, Advanced Info +@comment node-name, next, previous, up +@section Tag Tables for Info Files + + You can speed up the access to nodes of a large Info file by giving +it a tag table. Unlike the tag table for a program, the tag table for +an Info file lives inside the file itself and is used +automatically whenever Info reads in the file. + + To make a tag table, go to a node in the file using Emacs Info mode and type +@kbd{M-x Info-tagify}. Then you must use @kbd{C-x C-s} to save the +file. + + Once the Info file has a tag table, you must make certain it is up +to date. If, as a result of deletion of text, any node moves back +more than a thousand characters in the file from the position +recorded in the tag table, Info will no longer be able to find that +node. To update the tag table, use the @code{Info-tagify} command again. + + An Info file tag table appears at the end of the file and looks like +this: + +@example +^_ +Tag Table: +File: info, Node: Cross-refs^?21419 +File: info, Node: Tags^?22145 +^_ +End Tag Table +@end example + +@noindent +Note that it contains one line per node, and this line contains +the beginning of the node's header (ending just after the node name), +a Delete character, and the character position in the file of the +beginning of the node. + +@node Checking, Emacs Info Variables, Tags, Advanced Info +@comment node-name, next, previous, up +@section Checking an Info File + + When creating an Info file, it is easy to forget the name of a node +when you are making a pointer to it from another node. If you put in +the wrong name for a node, this is not detected until someone +tries to go through the pointer using Info. Verification of the Info +file is an automatic process which checks all pointers to nodes and +reports any pointers which are invalid. Every @samp{Next}, @samp{Previous}, and +@samp{Up} is checked, as is every menu item and every cross reference. In +addition, any @samp{Next} which does not have a @samp{Previous} pointing back is +reported. Only pointers within the file are checked, because checking +pointers to other files would be terribly slow. But those are usually +few. + + To check an Info file, do @kbd{M-x Info-validate} while looking at +any node of the file with Emacs Info mode. + +@node Emacs Info Variables, , Checking, Advanced Info +@section Emacs Info-mode Variables + +The following variables may modify the behaviour of Info-mode in Emacs; +you may wish to set one or several of these variables interactively, or +in your @file{~/.emacs} init file. @xref{Examining, Examining and Setting +Variables, Examining and Setting Variables, emacs, The GNU Emacs +Manual}. + +@vtable @code +@item Info-enable-edit +Set to @code{nil}, disables the @samp{e} (@code{Info-edit}) command. A +non-@code{nil} value enables it. @xref{Add, Edit}. + +@item Info-enable-active-nodes +When set to a non-@code{nil} value, allows Info to execute Lisp code +associated with nodes. The Lisp code is executed when the node is +selected. + +@item Info-directory-list +The list of directories to search for Info files. Each element is a +string (directory name) or @code{nil} (try default directory). + +@item Info-directory +The standard directory for Info documentation files. Only used when the +function @code{Info-directory} is called. +@end vtable + +@node Create an Info File, , Advanced Info, Top +@comment node-name, next, previous, up +@chapter Creating an Info File from a Makeinfo file + +@code{makeinfo} is a utility that converts a Texinfo file into an Info +file; @code{texinfo-format-region} and @code{texinfo-format-buffer} are +GNU Emacs functions that do the same. + +@xref{Create an Info File, , Creating an Info File, texinfo, the Texinfo +Manual}, to learn how to create an Info file from a Texinfo file. + +@xref{Top,, Overview of Texinfo, texinfo, Texinfo: The GNU Documentation +Format}, to learn how to write a Texinfo file. + +@bye |